Electro-mechanical relays belong to a very broad technological field covering various signals, such as digital signals, DC voltage signals, AC signals, etc. Mechanical switches that are based on magnetic mechanisms to facilitate the switching function are known in the art. Many manufactures of the microwave mechanical and electromechanical switches utilize various spring arrangements to perform the switching function from one input to multiple outputs.
In the applicant's own approach, a combination of permanent magnets and electrical solenoids has been utilized to move connecting elements associated with push reeds to provide connection between input and outputs. The advantage of using a combination of magnets and solenoids over mechanical springs mechanisms is that such combination arrangements provide significantly greater switching life compared to the pure mechanical designs. For the purposes of the application the switching life is considered to be a number of cycles the switching function is carried out between input and output ports of a switch. Applicant's (Scientific Components Corporation) own switching devices provide a very substantial switching life of over 10 million cycles, compared to about 1-2 million cycles typical for the industry.
On the other hand, a drawback of pure springless or frictionless mechanisms of the prior art is that in order to maintain a continuous switch function, a user needs to constantly apply a voltage or a signal to electrical solenoids forming a part of the switch. Otherwise such switches naturally revert back to their original state. This approach is not always beneficial to users who are selecting a predetermined switch position and wish to retain such position for an extended period of time. Furthermore, the voltage has to be constantly delivered to the switching device to keep the solenoid active. This results in undesirable heat generation and wasted power consumption.
Thus, it has been long felt and unsolved need to provide a latching electromagnetic RF switch operated without use of mechanical mechanisms and adapted to hold the switch in a desired state after a pulse of current has been removed from a solenoid.